Not only the content doesn't exist yet, it's just not practical. Even now 4k broadcasting is rare and 4k streaming is now a premium (and not always with a good bitstream, which matters a lot more) when once was offered as a cost-free future, imagine 8k that would roughly quadruple the amount of data required to transmit it (and transmit speee is not linear, 4x the speed would probably be at least 8x the cost).
And I seriously think noone except the nerdiest of nerds would notice a difference between 4k and 8k.
This is just weird. Why make these changes? Customers don't want it, the company doesn't profit and they actually lost money and reputation by doing this and not backtracking. Who is benefiting from this? It looks like a perfect lose-lose situation